Preheat has grill to medium high heat, or prepare a medium hot fire in a charcoal grill. To make the sage butter, but the tops off the garlic bulbs and place on a sheet of heavy-duty aluminum foil large enough to wrap both bulbs. Drizzle 2 Tbsp. of olive oil over the top. Wrap completely in the foil and place on the grill. Roast for about 40 minutes, remove from grill adn let cool. Squeeze the cooled roasted garlic into a mixing bowl, add in capers and smash with the back of a spoon until a paste forms. Add in the butter, cream cheese, minced sage leaves, and 1/2 tsp. kosher salt, mix well. Set aside. To make the patties, add ground chuck to a large mixing bowl. Finely grate the onion into the meat being sure to add in all the onion juice, add in soup mix and 2 1/2 tsp. kosher salt; mix gently until combined. Divide the mixture into 6 equal portions and then form into 6 oblong patties to fit the rolls. Keep patties covered and cool until ready to grill. To prepare the zucchini, slice the zucchini lengthwise into 5-inch long, 1/4-inch thick slices for a total of 12 slices. Arrange zucchini slices on top of paper towels and sprinkle with 1/2 tsp. kosher salt. Allow to sit for about 10 minutes to draw out the moisture. Press down with paper towels to extract moisture. Cut each Muenster cheese slice into 4 equal strips. Build the zucchini stacks as follows: Layer two strips of Muenster cheese and then top with another zucchini slice, don't let the cheese or proscuitto hang over the edge of the zucchini. Repeat to make remaining zucchini stacks. Place beaten eggs into a large bowl. Place flour seasoned with remaining tsp. kosher salt on a large plate. Dip zucchini stack, holding securely, into egg mixture and then flour mixture. Repeat with remaining zucchini stacks. Add remaining 1/4 cup olive oil to a medium non-stick fireproof skillet, place on the grill until hot. Cook zucchini stacks, three at a time, about 2 minutes on each side until nice and brown. Remove from skillet to paper towel lined plate. Repeat with remaining zucchini stacks. Now cook your patties. Brush the grill rack with vegetable oil. Place the patties on the grill rack, cover and cook, turning once, until done to your preference, 4 to 6 minutes on each side for medium. When patties are almost done, place the rolls, cut side down on the edge of the grill or top rack. Cover grill until rolls are toasted and light brown. To assemble the burgers, slather a generous amount of the sage butter on the cut sides of both the top and bottom of the rolls. On each roll bottom, layer on a patty, and a zucchini stack. Add the roll tops and serve.